Mozilla Foundation Security Advisory 2009-34

Crashes with evidence of memory corruption (rv:1.9.1/1.9.0.12)

Announced

July 21, 2009

Reporter

Mozilla developers and community

Impact

Critical

Products

Firefox

Fixed in

Firefox 3.0.12

Firefox 3.5

Description

Mozilla developers and community members identified and fixed
several stability bugs in the browser engine used in Firefox and other
Mozilla-based products. Some of these crashes showed evidence of
memory corruption under certain circumstances and we presume that with
enough effort at least some of these could be exploited to run
arbitrary code.

Workaround

Disable JavaScript until a version containing these fixes can be
installed.

References

Martijn Wargers, Arno Renevier, Jesse Ruderman, Olli Pettay and
Blake Kaplan reported crashes in the Firefox 3 and Firefox 3.5 browser
engines. monarch2020 reported an integer overflow in a base64
decoding function. Christophe Charron reported a crash occuring when
multiple RDF files were loaded in a XUL tree element. Yongqian Li
reported that a document can be constructed whose internal
representation contains double copies of certain elements leading to
potentially unsafe memory conditions. John Senchak also separately
reported a double frame construction bug which could also be used to
crash the browser and run arbitrary code.